Build is broken:
telemetry_unittests on Windows-7-SP1

Revision range:
chromium 399198 : 399204

Failing builders:
Win7 Tests (dbg)(1): https://build.chromium.org/p/chromium.win/builders/Win7%20Tests%20(dbg)(1)




telemetry.page.page_run_end_to_end_unittest.ActualPageRunEndToEndTests.testRaiseBrowserGoneExceptionFromRestartBrowserBeforeEachPage

  Successfully shut down browser cooperatively
  Traceback (most recent call last):
    File "e:\b\swarm_slave\work\isolated\isolated_runekl8te\third_party\catapult\telemetry\telemetry\page\page_run_end_to_end_unittest.py", line 176, in testRaiseBrowserGoneExceptionFromRestartBrowserBeforeEachPage
      story_runner.Run(test, story_set, options, results)
    File "e:\b\swarm_slave\work\isolated\isolated_runekl8te\third_party\catapult\telemetry\telemetry\internal\story_runner.py", line 225, in Run
      _RunStoryAndProcessErrorIfNeeded(story, results, state, test)
    File "e:\b\swarm_slave\work\isolated\isolated_runekl8te\third_party\catapult\telemetry\telemetry\internal\story_runner.py", line 77, in _RunStoryAndProcessErrorIfNeeded
      state.WillRunStory(story)
    File "e:\b\swarm_slave\work\isolated\isolated_runekl8te\third_party\catapult\telemetry\telemetry\page\shared_page_state.py", line 209, in WillRunStory
      'Should not restart browser when tracing is already running. For '
  AssertionError: Should not restart browser when tracing is already running. For TimelineBasedMeasurement (TBM) benchmarks, you should not use startup_url. Use benchmark.ShouldTearDownStateAfterEachStoryRun instead.